Ed Haggar, who coined the term "slacks," has died. From the Dallas Morning News obit:Yeah, but, women wear slacks; men wear trousers. See:Mr. Haggar teamed with legendary Dallas advertising pioneer Morris Hite to coin the term "slacks," his son said. Pants were largely known as trousers until then.....
"During the war years, people tried to get more casual during the weekends, during slack time or down time," [his son] Eddie Haggar said. "Dad and Morris Hite...came up with the name slacks."
Katharine Hepburn, Cary Grant, and James Stewart, on the set of The Philadelphia Story, 1940. Hepburn is wearing slacks. Grant and Stewart are wearing trousers. (And Grant is wearing white socks -- with a pin-striped suit. Who'd ever believe it could happen?)